Acute pancreatitis (AP) is among the most common hospital gastrointestinal diagnoses; understanding the mechanisms underlying the severity of AP is critical for development of new treatment options for this disease. Here, we evaluate the biological function of phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) in AP pathogenesis in 2 independent genetically engineered mouse models of AP. PFKFB3 was elevated in AP and severe AP (SAP), and KO of Pfkfb3 abrogated the severity of alcoholic SAP (FAEE-SAP). Using a combination of genetic, pharmacological, and molecular studies, we defined the interaction of PFKFB3 with inositol 1,4,5-trisphosphate receptor (IP3R) as a key event mediating this phenomenon. Further analysis demonstrated that the interaction between PFKFB3 and IP3R promotes FAEE-SAP severity by altering intracellular calcium homeostasis in acinar cells. Together, our results support a PFKFB3-driven mechanism controlling AP pathobiology and define this enzyme as a therapeutic target to ameliorate the severity of this condition.
3D printed phantom with 12 000 submillimeter lesions to improve efficiency in CT detectability assessment
AbstractBackgroundThe detectability performance of a CT scanner is difficult to precisely quantify when nonlinearities are present in reconstruction. An efficient detectability assessment method that is sensitive to small effects of dose and scanner settings is desirable. We previously proposed a method using a search challenge instrument: a phantom is embedded with hundreds of lesions at random locations, and a model observer is used to detect lesions. Preliminary tests in simulation and a prototype showed promising results.PurposeIn this work, we fabricated a full‐size search challenge phantom with design updates, including changes to lesion size, contrast, and number, and studied our implementation by comparing the lesion detectability from a nonprewhitening (NPW) model observer between different reconstructions at different exposure levels, and by estimating the instrument sensitivity to detect changes in dose.MethodsDesigned to fit into QRM anthropomorphic phantoms, our search challenge phantom is a cylindrical insert 10 cm wide and 4 cm thick, embedded with 12 000 lesions (nominal width of 0.6 mm, height of 0.8 mm, and contrast of −350 HU), and was fabricated using PixelPrint, a 3D printing technique. The insert was scanned alone at a high dose to assess printing accuracy. To evaluate lesion detectability, the insert was placed in a QRM thorax phantom and scanned from 50 to 625 mAs with increments of 25 mAs, once per exposure level, and the average of all exposure levels was used as high‐dose reference. Scans were reconstructed with three different settings: filtered‐backprojection (FBP) with Br40 and Br59, and Sinogram Affirmed Iterative Reconstruction (SAFIRE) with strength level 5 and Br59 kernel. An NPW model observer was used to search for lesions, and detection performance of different settings were compared using area under the exponential transform of free response ROC curve (AUC). Using propagation of uncertainty, the sensitivity to changes in dose was estimated by the percent change in exposure due to one standard deviation of AUC, measured from 5 repeat scans at 100, 200, 300, and 400 mAs.ResultsThe printed insert lesions had an average position error of 0.20 mm compared to printing reference. As the exposure level increases from 50 mAs to 625 mAs, the lesion detectability AUCs increase from 0.38 to 0.92, 0.42 to 0.98, and 0.41 to 0.97 for FBP Br40, FBP Br59, and SAFIRE Br59, respectively, with a lower rate of increase at higher exposure level. FBP Br59 performed best with AUC 0.01 higher than SAFIRE Br59 on average and 0.07 higher than FBP Br40 (all P < 0.001). The standard deviation of AUC was less than 0.006, and the sensitivity to detect changes in mAs was within 2% for FBP Br59.ConclusionsOur 3D‐printed search challenge phantom with 12 000 submillimeter lesions, together with an NPW model observer, provide an efficient CT detectability assessment method that is sensitive to subtle effects in reconstruction and is sensitive to small changes in dose.
Risk factors for implantable cardioverter defibrillator in patients with premature ventricular contractions in Olmstate County
Background: Premature ventricular contractions (PVCs) are associated with an increased risk of implanting implantable cardioverter defibrillator (ICD). Therefore, our study aimed to predict the risk factors for implantable cardioverter defibrillator in patients with premature ventricular contractions. Methods: A total of 309 patients (male 57%, mean age 66.73±16.12) in Olmstate Countywho had premature ventricular contractions and received a 24-hour electrocardiography monitoring were included between January 1994 and September 2010 at Mayo Clinic, Rochester, Minnesota. All these patients were continuously followed o Jun 2015. Student’s t-test, Chi-square, univariate and multivariate Logistic regression models were used to estimate the relationship between the risk factors and the incidence of implanting implantable cardioverter defibrillator (ICD) in PVCs patients. Kaplan–Meier curve of survival in PVCs patients with ICD or free-ICD. Results: The average follow-up time was 9.3±3.9 years, in which 43 (13.9%) patients died and 24 (7.8%) patients had received ICD therapy. Sex, age, pulse pressure, early repolarization syndrome (ERS), heart rate, PVC coupling interval, QRS duration, left ventricular ejection fraction (LVEF), left ventricular end-diastolic dimension (LVEDD) and left ventricular end-systolic dimension (LVESD), diabetes were significantly associated with the mortality and the incidence of implanting ICD. Using a multivariate logistic regression model adjusted for potential confounders, showed that LVEF (OR=0.916, 95% CI:0.881 to 0.953, p<0.001) and pulse pressure (OR=1.032, 95% CI:1.001-1.064, p=0.045) were independent factors for ICD implant in PVCs patients. Moreover, implantation of ICD may not reduce mortality in patients with ventricular premature. Conclusions: Increased pulse pressure was associated a higher incidence of ICD in PVCs patients, among many electrocardiographic and clinical variables studied. We also showed that PVs patients with ICD were at high risk of death, and the great pulse pressure was linked with higher morality in PVCs patients.
Extrachromosomal DNA Couples with ATM-mediated DNA Damage Response for Genome Instability in Tumors
Abstract Extrachromosomal DNA (ecDNA) drives the evolution of cancer cells by conferring survival advantages over normal cells. However, the functional importance of ecDNA replication and maintenance is yet to be evaluated, and the molecular components that contributed to these processes remain largely unknown. Here, using CRISPR-C (circularization of genes and chromosomes by CRISPR) technology and synthetic circular DNA mimicking ecDNA identified in tumors, we generated ecDNA-positive (ecDNA+) cell models. Using these models, we identified the proteins involved in ecDNA replication and maintenance and found DNA damage response (DDR)-related pathways were significantly enriched. We further demonstrated that ecDNA replication led to increased DDR and genome instability and DDR was also essential for ecDNA maintenance, consistent with observations that ecDNA+ tumors exhibited higher DDR scores than ecDNA-negative (ecDNA–) tumors in patients. ATM, MDC1, and CHK2, but not ATR, were activated in ecDNA+ cells compared to ecDNA– cells. Moreover, ecDNA+ cells were more sensitive to ATM and CHK2 inhibition. We further found that type II topoisomerase TOP2B and DNA ligase III (LIG3) were critical regulators for ecDNA replication and maintenance and related DDR. In summary, our findings of the reciprocal interactions between ecDNA and DDR provide new insights into detection and therapy for ecDNA+ tumors.
Longitudinal genetically detectable minimal residual disease by fluorescence
in situ
hybridization confers a poor prognosis in myeloma
Background: Deeper depth of response (DpR) after induction therapy, especially gain of negative minimal residual disease (MRD), has been linked to prolonged survival in multiple myeloma (MM). However, flow-MRD examination focuses on the numbers but not on the biological characteristics of residual plasma cells (PCs). Objectives: To explore whether the genetic features of residual tumor cells affect the survival time of patients with MM. Design: A retrospective cohort study. Methods: We investigated the clonality of cytogenetic abnormalities (CAs) of the residual PCs using interphase fluorescence in situ hybridization (iFISH) in the National Longitudinal Cohort of Hematological Diseases in China (NCT04645199). Here, a longitudinal cohort of 269 patients with patient-paired diagnostic and post-induction iFISH results was analyzed. Results: Persistent CAs after induction therapy were detected in about half of the patients (118/269, 43%), and patients with undetectable CAs showed significantly improved survival compared with those with genetically detectable MRD [median progression-free survival (mPFS): 59.7 versus 35.7 months, p < 0.001; median overall survival (mOS): 97.1 versus 68.8 months, p = 0.011]. In addition, different patterns of therapy-induced clonal evolution were observed by comparing the clonal structure of residual PCs with paired baseline samples. Patients who maintained at a high risk during follow-up had the worst survival (mPFS: 30.5 months; mOS: 54.4 months), while those who returned to lower risk or had iFISH− at both time points had the best survival (mPFS: 62.0 months, mOS: not reached). Conclusion: These findings highlighted the prognostic value of genetic testing in residual tumor cells, which may provide a deep understanding of clonal evolution and guide clinical therapeutic strategies.
Favorable Outcomes of Splenic Marginal Zone Lymphoma in an International Study of 934 Patients with Long Follow-up
Introduction: Splenic marginal zone lymphoma (SMZL) is a rare, indolent disease. There is no universally accepted standard therapy and long-term outcome data are limited. Rituximab monotherapy is increasingly used over splenectomy in the first-line setting despite a paucity of comparative studies. In the absence of randomized trials, large-scale international real-world data studies are critical to evaluate outcomes of different treatment interventions and to understand the natural history of SMZL in the rituximab-era. Methods: Adult patients with SMZL diagnosed between Jan 1 st 2000 and Dec 31 st 2018 were identified using regional/nationwide population-based registries or hospital registries in Europe, the UK, North America, and Australia. Medical records and pathology reports from eligible patients were reviewed locally by clinicians with specialty experience in hemato-oncology. SMZL cases were required to meet the diagnostic criteria by Matutes et al. Detailed data on clinico-pathological features, comorbidities, treatments (including treatment intention), treatment responses and survival outcomes were entered in a central study database. Overall survival (OS) was defined as time from diagnosis until death from any cause or censoring at last follow-up unless stated otherwise. Event-free survival (EFS) was defined as the time from diagnosis until histological transformation, initiation of new chemotherapy or death from any cause. Survival probabilities were estimated using the Kaplan-Meier estimator. Cumulative risk of transformation was estimated with death as a competing risk. Primary endpoints were 10-year OS and 5-year EFS respectivly. Results: A total of 934 patients from 25 sites were included. Median age at diagnosis was 68 years (IQR 60-76) and 54% were female. Bone marrow involvement was present in 96% (564/590) of those assessed, anemia (Hb <12g/dL for women or <13g/dL for men) in 58%, LDH >UNL in 46%, lymphocytosis (>5 x10 9/L) in 34%, and B-symptoms in 34%. Treatment data were available for 97% of patients. Median follow-up was 9.1 years (range 0-23). Watch and wait was the initial strategy in 28% and 88% of patients received at least one line of treatment during follow-up with the most common being splenectomy (45%), immuno-chemotherapy (19%) or rituximab monotherapy (8%). Fifteen percent received “other” treatments (i.e., combinations of listed therapies and/or radiation). The overall response rate to first-line treatment was 88% (95%CI: 85-90%) with 61% (95%CI: 57-64%) achieving CR. Second line (2L) therapy was needed in 34% during follow-up, 3L in 20% and 4L+ in 9%. The 5-year EFS and OS for all patients were 61% (95%CI: 57-65%) and 77% (95%CI: 74-80%) respectively. The 10-year OS and lymphoma-specific mortality (with non-SMZL deaths as competing risk) estimates were 60% (95%CI: 57-64%) and 11% (95%CI: 9-14%) respectively. The 5-year OS after 2L and 3L were 61% (95%CI: 55-68%) and 51% (95%CI: 42-61%) respectively (figure 1). The 10-year cumulative risk of histological transformation was 17% (95%CI: 13-21%), with 5-year post-transformation OS of 42% (32-54%). At the time of transformation, 60% were chemo-naive and 52% had never been treated for SMZL. The 5-year OS for chemo-naive patients with transformation was 54% (95%CI: 41-71%) versus 24% (95% CI: 13-44%) for transformations after (immuno)chemotherapy (p = 0.01). When comparing patients intended for treatment in first line with splenectomy (n=312) versus rituximab (n=70), patients treated with splenectomy more frequently presented with extra-hilar lymphadenopathy (35% vs 18%), splenomegaly (92% vs 87%) and anemia (64% vs 48%). OS was similar for the two groups (Figure 2, p = 0.53). The 5-year EFS were 63% (95%CI: 57-68%) and 64% (95%CI: 54-77%), respectively (p = 0.31). Conclusions: To date, this is the largest real-world study of SMZL with detailed treatment and outcome data. The study shows that histological transformation was not uncommon with 10-year risk of 17%. However, outcomes for the entire cohort were excellent irrespective of initial treatment and both OS and EFS were similar after first line rituximab versus splenectomy. Long-term survival remained relatively high even following multiple lines of therapy.
Assessment of Outcomes of Consolidation Therapy By Number of Cycles of Blinatumomab Received in Newly Diagnosed Measurable Residual Disease Negative Patients with B-Lineage Acute Lymphoblastic Leukemia: In the ECOG-ACRIN E1910 Randomized Phase III National
Introduction: ECOG ACRIN E1910 is a randomized phase III trial that showed that adults with newly diagnosed BCR::ABL1 negative acute lymphoblastic leukemia (ALL) who become MRD negative (<0.01%) after induction chemo who receive blinatumomab with conventional chemotherapy (chemo) have improved survival compared with those who received chemo only (Litzow et al, Blood (2022) 140: Supplement 2, LBA-1). However, not all pts were able to receive all four planned cycles of blinatumomab in consolidation. In this report we assessed outcomes of pts in the blinatumomab arm of the trial who received all 4 cycles of blinatumomab compared to those who received 1-2 cycles. Methods: Patient between the ages of 30 and 70 with newly diagnosed BCR::ABL1 negative B-lineage ALL were enrolled and initially received 2.5 months of combination induction chemo utilizing a BFM-like regimen adapted from the E2993/UKALLXII clinical trial, with pegaspargase (after induction only for patients >=55 years of age) and addition of rituximab for CD20 positive patients. After remission induction (step 1) pts in morphologic complete remission (CR/CRi) received an intensification course of high dose methotrexate with pegaspargase for CNS prophylaxis (step 2). At the conclusion of step 2, remission and MRD status were determined centrally by 6-color flow cytometry with MRD negativity defined as <0.01%. In the primary analysis subset, MRD negative patients were randomized to receive an additional 4cycles of consolidation chemo or 2 cycles of blinatumomab at 28 mcg/day (flat dose) for 28 days each cycle followed by 3 cycles of consolidation chemo, another 4-week cycle of blinatumomab (3rd cycle of blinatumomab) followed by an additional cycle of chemo and then a 4th cycle of blinatumomab (step 3). Following completion of consolidation chemo +/- blinatumomab, pts were given 2.5 years of POMP maintenance therapy timed from the start of the intensification cycle (step 4). Estimates of OS were calculated using the Kaplan-Meier method. Comparison of OS between treatment arms were conducted using the stratified log-rank test and Cox proportional-hazards model with age, CD20 status, rituximab use, and whether pts intend to receive HSCT or not as stratification factors. As the number of cycles needed to optimize outcome has not been studied, an unplanned landmark analysis was used to compare OS of pts in the blinatumomab arm who received all 4 cycles o those who received 1-2 cycles. Time 0 was chosen as 9 months post step 3 randomization (the time that patients were supposed to complete 4 cycles of blina). Four pts who received blinatumomab but died within 9 months post step 3 randomization were therefore excluded from this analysis. Results: The study was activated on December 17, 2013 and closed to enrollment on October 15, 2019. 772 pts were screened for the trial and 488 were enrolled on step 1 induction therapy. The median age of the pts was 51 years (range 30-70). 224 MRD negative pts were randomized, 112 pts to each arm. In the blinatumomab arm 12 pts received 1 cycle (11%), 32 pts received 2 cycles (29%), 4 pts received 3 cycles (4%) and 63 pts received 4 cycles (57%). The OS of pts who received 1-2 cycles of blinatumomab was compared to control (Figure 1) The difference was not significant (hazard ratio 0.62, 95% CI 0.28 to 1.34, p=0.22). Fig 2 compares the survival of those who received 1-2 cycles to those who received 4 cycles ( (HR: 0.39, 95% CI 0.12 to 1.16, p=0.076). Conclusion: The addition of blinatumomab to consolidation chemotherapy resulted in a significantly better overall survival compared to chemotherapy alone in pts with newly diagnosed B-lineage ALL who were MRD negative after intensification. This represents a new standard of care for pts aged 30-70 years with BCR::ABL1 negative ALL. The optimal dose and number of cycles is however unknown. In this unplanned subgroup analysis we demonstrate that a survival benefit can only be confirmed in patients who receive the intended 4 cycles of blinatumomab during consolidation. Further studies will be needed to determine if fewer cycles can provide a similar benefit.
Comparing in vivo wave-based elastography with ex vivo mechanical testing in porcine vessels
Arterial stiffness predicts cardiovascular disease, the leading cause of death worldwide. Ultrasound elastography methods that measure wave velocity have promise for evaluating the stiffness of blood vessels in vivo. However, vessel geometry modulates wave velocity by inducing geometric dispersion. Here, we compare Young's modulus E estimates obtained using in vivo wave velocity measurements and techniques that either do or do not consider geometry to ex vivo reference E values from mechanical testing . An acoustic radiation force was applied to generate propagating waves in the right common carotid artery (N = 9) and external jugular vein (N = 10) of anesthetized pigs. Vessels were imaged with ultrafast ultrasound to measure wave motion. Group velocity cg was estimated from wave motion using a Radon transform. E was estimated from cg using a bulk media assumption which neglects geometry, as well as the Moens–Korteweg equation and a semi-analytical finite element model, which consider geometry. Pigs were euthanized and vessels were excised. Ring-shaped samples were extracted and tested in a uniaxial tension setup to obtain reference E values for comparison with E values obtained from wave-based techniques. Techniques considering geometry exhibited higher correlation with reference E values, underscoring the need to incorporate geometry for accurate vascular elastography assessments.
Concurrent TERT promoter C228T and C250T mutations in diffuse gliomas: Rare occurrence of intratumoral heterogeneity
A 74-year-old male presented with rectal pain; workup uncovered an anal mass, and a diagnosis of melanoma was rendered via histologic examination and immunohistochemical (IHC) studies. Droplet digital PCR (ddPCR)–based BRAF testing was performed and revealed the presence of BRAF V600E, which is a common targetable genetic alteration in melanoma. Interestingly, the ratio of mutant to wild-type copy number was low (0.3%), whereas tumor cell percentage on tissue slides was 90%. With additional workup, BRAF V600E IHC confirmed a very small subset of BRAF V600E–positive cells, and a next-generation sequencing (NGS) panel revealed a pathogenic KIT variant, p.L576P, with an allele frequency of 63%. It was initially hypothesized that the main driver of the melanoma was the KIT alteration, whereas a small subclone (not detected by NGS, which has a 5% limit of detection) was driven by the BRAF V600E detected by ddPCR. To determine whether there were morphologic differences between the 2 clones, a careful review of the histology was performed and revealed distinct morphology of the BRAF V600E–positive cells, including pale cytoplasm, nuclear grooves, and infiltrating eosinophils. Additional IHC workup of the BRAF V600E–positive cells showed coexpression of CD1a, Langerin, and S100, diagnostic of Langerhans cell histiocytosis (LCH). This diagnosis was unexpected and would have been missed without highly sensitive molecular testing; yet it is of clinical importance for the patient. This case raises interesting biology questions regarding the relationship between melanoma and LCH; moreover, it highlights the importance of integrating quantitative information in molecular data interpretation.